Rotary rock bit



Feb. 5, 1935. J. w. SPERRY 1,990,007

ROTARY ROCK BIT Filed Oct. 20, 1950 2 Sheets-Sheet 1 v i A3 A. 5,40 )5 E l4 i f/vvz/vroe: James 14 Sperry, 49 5) Y Arrrmmsx Feb. '5, 1935. .1. w. SPERRY 1,990,007 I ROTARY ROCK BIT Filed Oct. 20, 1930 2 Sheets-Sheet 2 IND-mm James W Sperry,

A TTORNE'X Patented Feb. 5,1935

UNITED STATES PATENT OFFICE ROTARY-ROCK Brr James W. Sp rry, San Marino, Calif. Application October 20, 1930,'Serial No. 49,931 9 Claims. (01. 255-71) My invention relates to drilling bits for use in a constant cleaning of the bit rollers by the jets boring holes in hard formations and relates parof drilling fluid. ticularly to roller rock bits which penetrate by Further objects and advantages of 'the inventhe crushing action of the rollers. ti will app r hr u h ut h following part I In the oil well drilling industry roller bits now of the specification. 5

employed consist essentially of two types, the Referring to the drawings, which are for illusconical roller type and the cylindrical roller type, trative purposes only, I the rollers of which are provided with teeth or Fig. 1 is a partly sectioned elevational view of a ridges which crush the surface portion of the forpreferred embodiment of my invention. mation against which the rollers are operated F 2 iS a t P ew Of 1 With One 10 with a disintegrating action. of the rollers and its bearing structure removed. My invention relates to the construction of bits Fig- 3 i a fr gm nt y c i l vi w wi of this character rather than to the principles of an alternative interlocking construe J operation, and it is an object of the invention to g- 4 is e ry Sectional V Showing 5 provide a rotary bit structure having a one-piece an additional method of securing the bearing bit body instead of the two-piece bit body extenstructures to the bit body. sively used for well drilling, and it is a further Fig. 5 is a section taken on a pl n represented object to provide a simple, yet entirely safe and y t e line 5-5 of F g. 4. practical means for securingthe rollers to the 6 Shows the manner in which the grooves one-piece bit body. may be placed radially instead of tangentially. 20

A further object is to provide a securing means Fi 7 is a m ntary s tional vi w showin for the rollers which will not permit the rollers to a a a v r f wat r urs p ot ct rbecome lost in the well, but which is of such Referring to Figs- 1 n I p y a solid or character that when the bit is removedfrom the -p e bit y 11 dap to b Secu ed to well, the rollers may be easily removed and rea String of drill D D drill St m A e 5 placed or resharpened. lower end of the bit 11 a pair of short legs 13 are A further object of the invention is to provide formed. these legs having d a y di cted a d a roller bit having m an f r k i th t th, inwardly faced surface portions 14 adjacent which or grooves of the rollers clean, thereby maintainconical rollers 15 are Secured- Althellgh'the angle "ing a maximum cutting emciency t all times at which the surface portions 14 are extended 30 during the operation of the b t, may vary, I have found it generally advisable to It is also an object of the invention to provide P a the Surface Portions 14 at angles of pp a single-piece bit body a d removable bearing mately 45 to the axis of rotation A-A of the bit structures for the rollers, these bearing strucbody 11, and to make the conical rs With an fibres being secured to the bit body by the use external angle of p of interlocking or tongue and groove members As shown in Fig. 1, each conical roller 15 is so constructed that the rollers may be readily insupported by a bearing structure having an. stalled on and removed from the bit body. axis on which the conical roller 15 i Another object of the invention is to provide tatably supported- This s s p efe ab y 46 a bearing structure which does not require lubri normal or perpendicular to the face portion 14. eating systems having pressure f ed n cylinders The axes BB, where a substantially true and and the like, but which may be packed with1ubri rolling condition is to be attained, should intercant more than suflicient for a single run of the sect at pohit P on the axis Each roller mnem 15 has a conical recess 17 threaded at 18 to re- A Still firth b ceive a ring 19 which holds the roller 15 on a 45 er the inventmn is pm conical bearing block 20: Fdonical bearing bit having protect-ed water course channels block is bored and threaded left-hand as shown i f g f fi f there" at 21, to receive a threaded pin 22 having an m W1 eep e ers F c interlockingbody 23 formed (in its upper end for A feature the mvention 15 to Protect thgse engagement-with a groove or channel 24 formed 0 water course channels with replaceable inserts in the urf e portion The interlocking body which will take the wear, prevent enlargement has upper and lower edge portions 26 and 7 0f the water 0011186 channels and maintain the which may be conveniently made of dovetail form, alignment of the jets of drilling fluid with re-- as shown, and the groove 24 is confined between spect to the cutters, in manner maintaining edge walls 28 which cooperates with edge por- 55.

tions of the body 23. The tongue and groove interlocking parts thus formed can be moved relative to each other only in one direction. I direct the groove 24 tangentially with respect to a circle about the axis AA and normal to the axis BB. A counterbored opening 30 is formed in the leg 13 to permit a locking device, such as a screw 31 to be screwed intoxthe interlocking body 23 and the threaded pin 22 in the manner shown, thereby preventing tangential movement of the bearing structure 16, which includes parts 20 and 22, relative to the bit body 11. Adjacent to a face 33 of the conical body 20 I place a bearing ring 34 which is clamped between the conical body 20 and the interlocking body 23 when the conical body 20 is screwed on the pin 22.

The bearing structure 16 and the roller 15 are assembled before being mounted on the bit body- 11. A quantity of lubricant, such asheavy grease, is placed in the recess 17 and the conical bearing body 20 is then placed in the conical recess 17 and the .holding ring 19 is screwed in place so as to occupy the annular groove 36 adjacent to the upper face 33 of the conical bearing body 20. The wear ring 34 is then placed in concentric position on the face 33 and a pin 38 is caused to engage the conical body 20 and the wear ring 34 in such a manner that the holding of the wear ring will prevent rotation of the conical bearing body 20 while the pin 22 is being screwed into the threaded bore 21. When the screw 22 has been screwed in to its full extent so that the interlocking body formed thereon is in tight engagement with the wear ring 34, the interlocking body 23 is slid into the groove 24 and the looking means consisting of the screw 31 is inserted and drawn up tight.

Although the edge walls 28 of the groove 24 may be extended parallel to each other, it is preferable to cause them to converge, as shown in Fig. 2, in a direction opposite to the direction of rotation of the bit body, thereby utilizing the torque which is transmitted from the bit body to the bearing structure 16 during the, operation of the bit, for the purpose of holding the interlocking body 23 and the bearing structure in tight engagement with the interlocking parts of the bit body.

As shown in Fig. 2, a, single opening 30 for a locking screw 31 may be provided for each bear ing structure 16 for smaller bits, but in bits of larger size it may be desirable to employ a pair of locking screws in the position indicated by dotted lines 40. The opening 30 may be made purposely larger than the screw 31 so as to permit a slight movement of the screw 31 when the interlocking body 23 is forced up tightly into the converging or tapered groove 24.

It is evident that with the pair of rollers 15 mounted in position for operation on the bit body 11, the conical bearing bodies 20 cannot be unscrewed from the pins 22, nor can the rollers 15 be removed from the conical bearing bodies. The movement between the interlocking body 23 and the groove 24 required for disengagement of the bearing structure 16 from the bit body 11 is so directed that, should the locking screw 31 be omitted or become lost in the well, movement of the interlocking body 23 in the groove 24 would result in an engagement of the forward end of the interlocking body 23 with the wall of the well and the reaction thereof during rotation of the bit would constantly tend to force the interlocking body 23 into the tapered groove 24, the result of this being that loss in the well of any part of the bit structure, other than the screw 31 and its locking nut, is practically impossible. My simple tongue and groove means for securing the bearing structures to the bit body 11 contributes to that feature of the invention relating to a one-piece bit body. The bit body, avoiding the use of a number of parts secured together by screws, is rigid, entirely safe to operate, and relatively economical in production.

For, securing the bit body to the drill pipe 12, I provide a threaded opening '45, and leading downwardly from the bottom 46 of the opening 45 are water coursechannels 47 and 48 directed respectively toward the right and left-hand rollers 15 so that the streams of drilling fluid issuing therefrom will travel through the surface slots 49 of the cutters and keep same washed clean from accumulations of cuttings. The openings 47 and 48 are protected by wear resistant liners 51 which project downwardly from a circular plate 52. The liners 51 and the plate 52 are preferably made from a rubber compoimd which will resist wear from abrasive particles carried in the drilling fluid and 'will protect the walls of the openings 4'7 and 48 so that they will not become disaligned or enlarged.

In Fig. 3 I show one leg 13' of'a bitbody 11' having a groove 24' therein of double dovetail form [a bearing pin 63 extends in pomtion to support a conical bearing body 64 for receiving a roller 65.

The dovetail body 62 consists of an inner portion 66 and a smaller outer portion 67, the outer portion being of a length L, as shown in Fig. 5. In

one end of the tapered groove 61 a block 70 is mounted, this block filling the cross section of the groove and being preferably secured inplace by the autogenous'welding method. A horizontally directed lock screw 71 passes through an opening 72 in the block 70 and the threaded forward end 73 thereof enters the dovetail body 62. The block 70 is counterbored at 75 to receive a head 76 of the screw 71, and a poly onal recess 77 is provided in the head 76 for engagement of a wrench by which to turn the screw 71. This screw 71 draws the dovetail body 62 tightly into the tapered groove 61 and holds it in this position during the operation of the bit. As shown in Fig. 6, a dovetail groove 78 may be cut in the lower portion of a bit body 80 in radial direction instead of tangentially; as previously described. The principles of the invention may be practiced in this manner, but it is not thought that the results obtained therefrom will be nearly so good as those obtained from the use of the tongue and groove interlocking means in tangential position and for the reason that the walls of the hole will serve to hold the parts in engagement should the locking screw be omitted or lost.

4 In Fig. 7 I show an alternative form of water course protector 82 having a flange 83 adapted to be received in a counterbore 84 of a water 84 is internally threaded, as indicated at 8'1, to I receive a. ring nut 89 having spanner wrench openings 90 therein to enable the ring 89 to be screwed down ti htly against the flange 83 to hold the water course protector 82.

In Figs. 1 and 2, I have shown the dovetail body 23 and the groove 24 both tapered. As a result of this design, the side walls 28 of the groove, be-

' ing convergent, serve as a definite stop means for preventing movement of the body 23 beyond a definite position. The resistance of the roller to the torque applied thereto from the bit body constantly forces the interlocking body 23 tightly, against the stop thus provided by the converging side wall 28. During the forward operationof the bit there is no actual need for the locking screw 31, as there are no forces exerted on the interlocking body, which would tend to move it out of the slot 24; therefore, there is little possibility of the bearing structure or cutter becoming lost in the well.

I claim as my invention:

1. A rotary rock bit, including: a bit body; a roller type cutter adapted for operation on said body; a bearing structure for operatively holding said cutter; and interlocking means for securing said bearing structure to said body, said interlocking means comprising cooperating parts on said body and said bearing-structure adapted to slide into interengagement in a direction tangential to a circle of rotation around the axis of rotation of said body.

2. A rotary rock bit, including: a bit body; a

roller type cutter adapted for operation on said body; a bearing structure for operatively holding said cutter; and interlocking means for securing said bearing structure to said body, said interlocking means comprising cooperating parts onsaid body and said bearing structure adapted to slide into interengagement in a direction non-parallel to the axis of said cutter and tangential to a circle of rotation around the axis of rotation of said body.

3. A rotary rock bit, including: a bit body; a roller type cutter adapted for operation on said body; a bearing structure for operatively holding said cutter; and interlocking means for securing said.bearing structure to said body, said interlocking means comprising cooperating parts on said body and said bearing structure adapted to slide into interengagement in a direction substan tially normal to the axis of said cutter and tangential to a circle of rotation around the axis of rotation of said body. Y

4. In a rock bit of the class described, the combination of: a body having a depending leg at one side thereof, said leg having an inner face; a

roller adapted for operation adjacent the inner face of said depending leg; a bearing structure within said depending leg for rotatably supporting said roller; and interlocking means for securing said bearing structure to said depending leg, said interlockingmeans including a tongue andgroove directed tangentially of a circle around the axis of rotation of said body, one of which is formed on said inner face of said depending leg, and the other of which is formed on said bearing structure.

5. A rotary rock bit, mousing a bit body; a roller adapted for operation on said body; a bearing structure for operatively holding said roller;

interlocking means forsecuring said bearing structure to said body, said interlocking means comprising cooperating parts on said body and said bearing structure adapted to slide into interengagement in a direction tangential to a circle of rotation around'the axis of rotation of said body, said interlocking means being tapered to provide a wedging of the parts thereof; and lock means to hold said cooperating parts of said body and said bearing structure together.

6. A rotary rock bit, including: a bit body having a pair of facing portions inclined relative to the axis of rotation of the body and forming a space therebetween; a pair of rollers each of which is adapted for operation on said body in position adjacent to one of said inclined portions on an axis substantially normal to such portion; a bearing structure for rotatably supporting each rol1er;' interlocking means, one of which is on each of said bearing structures and the other of which is on one of said inclined portions, for securing each bearing structure to such inclined portion, one of said means comprising a groove and the other of said means comprising a tongue making interlocking engagement with said groove, said tongue and groove being slidahle into engagement tangentially with respect to a circle of rotation around the axis of rotation of said body; and means for holding said interlocking means from relative movement in the direction of said tongue and groove.

'7. A rotary rock bit, including: a bit body having a pair of facing portions inclined relative to the axis of rotation of the body and forming a space therebetween; a pair of rollers each of which is adapted for operation on said body in position on an axis substantially normal to such portions; a bearing structure for rotatably supporting each roller; interlocking means, one of which is on each of said bearing structures and the other of which is on one of said inclined po us, for securing each bearing structure to such inclined portion, one of said means comprising a groove and the other of said means comprising a tongue making interlocking engagement with said groove, said tongue and groove being slidable into engagement tangentially with respect to a circle of rotation around the axis of rotation of said body and non-parallel to the axis of said bearing structure; and means for holding said interlocking means from relative movement in the direction of said tongue and ve.

8. A rock bit of the cha ter described, in-

cluding: a bit body having'a pair of downwardlyextending legs forming a space therebetween; a.

pair of roller. cutter members each of which is adapted for operation adjacent the inner face of one of said legs; a supporting structure for each of said roller cutter members; interlocking means for securing each of said supporting structures to. one of said legs, each'of said interlocking means consisting of two parts, one of which is on the supporting structure and the other of which is on the cooperating leg, one of said parts comprising a groove and the other of said parts comprising a tongue making interlocking engagement with said groove, said tongue and groove being slidable into engagementtapgentially with respect to a circle of rotational-blind the axis of rotation of said body; and means for holding said interlocking parts from rela tive movement in the direction of the tongue and groove.

9. A device as defined in claim 8, in which said tongue and groove are longitudinally tapered so as to be wedged together when in full engagement.

' JAMES W. SPERRY. 

